Genetic atypical hemolytic uremic syndrome in children: a 20-year experience from a tertiary center

• Autor(a) principal: Maximiano,Cristiana
• Data de Publicação: 2021
• Outros Autores: Silva,Andreia, Duro,Inês, Branco,Tiago, Correia-Costa,Liane, Teixeira,Ana, Rocha,Liliana, Costa,Teresa, Matos,Paula, Faria,Maria do Sameiro, Mota,Conceição, Afonso,Alberto Caldas
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Jornal Brasileiro de Nefrologia
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0101-28002021000300311
• topic: Atypical Hemolytic Uremic Syndrome; Child; Genetic Testing; Thrombotic Microangiopathies

Abstract Introduction: Atypical hemolytic uremic syndrome (aHUS) is a rare disorder characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury, which primarily affects preschool-aged children. This study’s aim was to describe the clinical profile, management, and long-term outcome of the genetic aHUS patients admitted to a tertiary care pediatric nephrology center during 20 years. Methods: We performed a retrospective analysis of the clinical records of all aHUS patients younger than 18 years with identified genetic mutations. Data on clinical features, genetic study, therapeutic interventions, and long-term outcomes were reviewed. Results: Five cases of aHUS with an identified genetic mutation were included; all were inaugural cases with the youngest being 4 months old. Complement factor H gene mutation was identified in four patients. Therapeutic plasma exchange was performed for acute management in 4 patients, one of whom also needed acute renal replacement therapy (peritoneal dialysis). All patients went on complete remission, 2 had more than one relapse but only 1 of these progressed to chronic kidney disease during the follow-up period (median (25th-75th percentile), 136 (43.5-200.5) months). Conclusion: In children, the prognosis of renal function seems to be strongly dependent on the genetic background, thus being crucial to perform genetic study in all aHUS cases. In our cohort, 2 patients presented genetic mutations not previously described. Recent innovations on the genetic field leading to the identification of new mutations has lead to a better understanding of aHUS pathogenesis, but further studies, focusing on the genotype-phenotype correlation, with longer follow-up periods, are needed.